build: remove more unneeded code from nix

Readme.org

@@ -620,23 +620,15 @@ The real question is: why is this not standard in Bash for Windows? Who knows. I
 
 ** Nix
 
-You can run this directly from github:
+To build a stand-alone binary:
 
 #+begin_src shell :results none :eval never-export
-nix run github:hraban/tomono
-#+end_src
-
-Or you can build a stand-alone binary:
-
-#+begin_src shell :results none :eval never-export
-nix build github:hraban/tomono#dist
+nix build .#dist
 #+end_src
 
 Find the binary in =./result/bin/=, and the documentation in =./result/doc=.
 
-Tip: to build local changes, substitute =github:hraban/tomono= with a single period (=.=).
-
-To test the code (this only really makes sense on a local checkout):
+To test the code
 
 #+begin_src shell :results none :eval never
 nix flake check .

flake.nix

@@ -70,13 +70,10 @@
                 env = {
                   GIT_AUTHOR_NAME = "Test";
                   GIT_AUTHOR_EMAIL = "test@test.com";
-                  GIT_COMMITTER_NAME = "Test";
-                  GIT_COMMITTER_EMAIL = "test@test.com";
                 };
                 nativeBuildInputs = [
                   # The actual code being tested. Must be in PATH.
                   self.packages.${system}.default
-                  pkgs.makeWrapper
                 ];
                 dontUnpack = true;
                 buildPhase = ''